2157886 has 4 divisors (see below), whose sum is σ = 3236832. Its totient is φ = 1078942.

The previous prime is 2157863. The next prime is 2157893. The reversal of 2157886 is 6887512.

It is a semiprime because it is the product of two primes.

It is a super-3 number, since 3×2157886³ = 30144407143339867368, which contains 333 as substring.

It is an Ulam number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 539470 + ... + 539473.

It is an arithmetic number, because the mean of its divisors is an integer number (809208).

2^2157886 is an apocalyptic number.

2157886 is a deficient number, since it is larger than the sum of its proper divisors (1078946).

2157886 is a wasteful number, since it uses less digits than its factorization.

2157886 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1078945.

The product of its digits is 26880, while the sum is 37.

The square root of 2157886 is about 1468.9744722084. The cubic root of 2157886 is about 129.2238965726.

The spelling of 2157886 in words is "two million, one hundred fifty-seven thousand, eight hundred eighty-six".